Chromatic dispersion compensating apparatus

Abstract

In order to compensate for chromatic dispersion ad dispersion slope over an entire wavelength band of the optical signal, the wavelength band is split into a plurality of bands, and chromatic dispersion compensation is made to make chromatic dispersion in a central wavelength of each of the bands zero.

1. A chromatic dispersion compensating apparatus for use in a wavelength-division multiplexed optical transmission system, comprising:
 a band splitting unit splitting a wavelength-division multiplexed optical signal into a plurality of wavelength bands, each wavelength band of the plurality of wavelength bands having a continuous wavelength band; 
 a variable dispersion compensating unit making compensation simultaneously for split wavelength multiplexed optical signals; and 
 an interleaving unit, which is arranged at a stage before said band splitting unit, separating the wavelength-division multiplexed optical signal, and converting the wavelength-division multiplexed optical signal into a plurality of optical signals whose channel intervals are widened. 
 
   
   
     2. The chromatic dispersion compensating apparatus according to  claim 1 , is arranged within a optical receiver. 
   
   
     3. The chromatic dispersion compensating apparatus according to  claim 1 , is arranged within an inline amplifier. 
   
   
     4. The chromatic dispersion compensating apparatus according to  claim 1 , wherein the inline dispersion compensation makes 105- to 120-percent compensation for chromatic dispersion that a received wavelength multiplexed optical signal undergoes. 
   
   
     5. The chromatic dispersion compensating apparatus according to  claim 1 , further comprising a band combining filter unit combining compensated optical signals from said variable dispersion compensating unit. 
   
   
     6. The chromatic dispersion compensating apparatus according to  claim 1 , further comprising an optical attenuator attenuating the compensated optical signals from said variable dispersion compensating unit. 
   
   
     7. A chromatic dispersion compensating apparatus for use in a wavelength-division multiplexed optical transmission system, comprising:
 an interleaving unit separating the wavelength-division multiplexed optical signal, and converting the wavelength-division multiplexed optical signal into a plurality of optical signals whose channel spacing is enlarged; 
 a plurality of band splitting units splitting a plurality of optical signals whose channel spacing is enlarged into a plurality of wavelength bands, each wavelength band of the plurality of wavelength bands has a continuous wavelength band; 
 a plurality of combining interleaver units combining the wavelength bands of the plurality of wavelengths bands; and 
 a plurality of variable dispersion compensating units making compensation simultaneously for split wavelength multiplexed optical signals. 
 
   
   
     8. A chromatic dispersion compensating apparatus for use in a wavelength-division multiplexed optical transmission system, comprising:
 a plurality of band splitting units splitting a plurality of optical signals whose channel spacing is enlarged and outputting a plurality of wavelength bands, each wavelength band of the plurality of wavelength bands having a continuous wavelength band; 
 a plurality of combining interleaver units combining the wavelength bands of the plurality of wavelengths, the wavelength bands being of the same band; and 
 a plurality of variable dispersion compensating units making compensation simultaneously for split wavelength multiplexed optical signals.